1. Field of the Invention
This invention relates to gas turbine engines and more particularly to the control of parameter setting devices for the engine.
2. Description of the Prior Art
Modern gas turbine engines have come to rely on sophisticated parameter variations throughout the engine operating cycle to optimize engine efficiency and stability over a wide range of power levels. The most commonly varied parameters include fuel flow, flowpath contour, and pressure along the flowpath. Numerous mechanical, pneumatic, electrical, hydraulic and electromechanical devices have been developed to meet the perceived operational and environmental requirements in variance of the parameters.
The accuracy of all prior developed parameter controlling devices is, of course, limited to the accuracy of sensing equipment within the control circuit for sensing physical intelligence such as the current position of the parameter controlling device. Engine designers and manufacturers have devoted substantial economic and valued personnel resources toward the development of improved sensing apparatus which can be made compatible with the hostile engine environment in which the sensing and control apparatus must operate. The concepts of the present invention are directed to further improved apparatus.